Abstract: TH-OR133
Self-Reported vs. Measured Physical Function in Kidney Transplant Candidates at the Top of the Waitlist
Session Information
- Policy and Pretransplant Considerations
November 07, 2019 | Location: 151, Walter E. Washington Convention Center
Abstract Time: 05:30 PM - 05:42 PM
Category: Transplantation
- 1902 Transplantation: Clinical
Authors
- Watford, Daniel J., Stanford University , Palo Alto, California, United States
- Cheng, Xingxing S., Stanford University , Palo Alto, California, United States
- Han, Jialin, Stanford University , Palo Alto, California, United States
- Stedman, Margaret R., Stanford University , Palo Alto, California, United States
- Chan, Khin N., Stanford University , Palo Alto, California, United States
- Myers, Jonathan N., VA Palo Alto Health Care System, Palo Alto, California, United States
- Tan, Jane C., Stanford University , Palo Alto, California, United States
Background
Poor physical function of waitlisted kidney transplant candidates is associated with adverse waitlist outcomes, but the optimal metric is not known. We compared self-reported versus measured functional assessments in patients at the top of the waitlist.
Methods
Patients were evaluated from May 2017 to December 2018. Self-reported SF36 physical function subscale score (SF36 PF) was compared to results of the 6-minute walk test (6MWT) and sit-to-stand (STS) test by linear regression. We estimated the association between each metric and time to adverse waitlist outcomes (waitlist removal or death), with transplant as the competing event, by the Fine-Grey model, and adjusted for clinical covariates. We estimated model fit by AIC and likelihood ratios and compared hierarchically nested models, starting with demographics and comorbidities and sequentially adding physical assessment metrics.
Results
Out of 200 patients, the median SF36 PF, 6MWT, and STS results were 80, 396 meters, and 18, respectively. Physical function metrics were highly correlated (R2=0.49 for STS-6MWT, 0.32 for STS-SF36 PF, and 0.54 for 6MWT-SF36 PF). Over median follow-up of 118 days, 29 patients were removed from the waitlist, 6 died, and 23 were transplanted. All three metrics were strongly associated with waitlist outcomes and improved model fit for adverse waitlist outcomes over standard exposures of demographics and comorbidities alone. 6MWT and SF36 PF results improved model fit more than STS. See figure.
Conclusion
Self-reported and measured assessments of physical function are strongly associated in kidney transplant candidates. Addition of SF36 and/or 6MWT results to standard exposures significantly improves association with waitlist outcomes. Combining self-reported and measured physical function metrics may provide the best assessment of global functional status in kidney transplant candidates.